VAULT-5280 add telemetry annotations for agent sidecar

agent-inject/agent/agent.go

@@ -297,6 +297,9 @@ type Vault struct {
 
 	// AuthMinBackoff is the maximum time to backoff if auto auth fails.
 	AuthMaxBackoff string
+
+	// AgentTelemetryConfig is the agent telemetry configuration.
+	AgentTelemetryConfig map[string]interface{}
 }
 
 type VaultAgentCache struct {
@@ -390,6 +393,8 @@ func New(pod *corev1.Pod) (*Agent, error) {
 		return agent, err
 	}
 
+	agent.Vault.AgentTelemetryConfig = agent.telemetryConfig()
+
 	agent.InitFirst, err = agent.initFirst()
 	if err != nil {
 		return agent, err

agent-inject/agent/annotations.go

@@ -1,6 +1,7 @@
 package agent
 
 import (
+	"encoding/json"
 	"fmt"
 	"path"
 	"strconv"
@@ -301,6 +302,11 @@ const (
 
 	// AnnotationAgentAutoAuthExitOnError is used to control if a failure in the auto_auth method will cause the agent to exit or try indefinitely (the default).
 	AnnotationAgentAutoAuthExitOnError = "vault.hashicorp.com/agent-auto-auth-exit-on-err"
+
+	// AnnotationAgentTelemetryConfig specifies the Agent Telemetry configuration parameters.
+	// The name of the parameter is any unique string after "vault.hashicorp.com/agent-telemetry-",
+	// such as "vault.hashicorp.com/agent-telemetry-foobar".
+	AnnotationAgentTelemetryConfig = "vault.hashicorp.com/agent-telemetry"
 )
 
 type AgentConfig struct {
@@ -759,8 +765,8 @@ func (a *Agent) setShareProcessNamespace(pod *corev1.Pod) (bool, error) {
 	if pod.Spec.ShareProcessNamespace != nil {
 		if !*pod.Spec.ShareProcessNamespace && shareProcessNamespace {
 			return DefaultAgentShareProcessNamespace,
-			errors.New("shareProcessNamespace explicitly disabled on the pod, " +
-				"refusing to enable it")
+				errors.New("shareProcessNamespace explicitly disabled on the pod, " +
+					"refusing to enable it")
 		}
 	}
 
@@ -834,6 +840,26 @@ func (a *Agent) injectToken() (bool, error) {
 	return strconv.ParseBool(raw)
 }
 
+// telemetryConfig accumulates the agent-telemetry annotations into a map which is
+// later rendered into the telemetry{} stanza of the Vault Agent config.
+func (a *Agent) telemetryConfig() map[string]interface{} {
+	telemetryConfig := make(map[string]interface{})
+
+	prefix := fmt.Sprintf("%s-", AnnotationAgentTelemetryConfig)
+	for annotation, value := range a.Annotations {
+		if strings.HasPrefix(annotation, prefix) {
+			param := strings.TrimPrefix(annotation, prefix)
+			param = strings.ReplaceAll(param, "-", "_")
+			var v interface{}
+			if err := json.Unmarshal([]byte(value), &v); err != nil {
+				v = value
+			}
+			telemetryConfig[param] = v
+		}
+	}
+	return telemetryConfig
+}
+
 func (a *Agent) authConfig() map[string]interface{} {
 	authConfig := make(map[string]interface{})
 

agent-inject/agent/annotations_test.go

@@ -1243,3 +1243,46 @@ func TestDisableKeepAlives(t *testing.T) {
 		})
 	}
 }
+
+func TestParseTelemetryAnnotations(t *testing.T) {
+	tests := map[string]struct {
+		annotations    map[string]string
+		expectedValues map[string]interface{}
+	}{
+		"prometheus": {
+			annotations: map[string]string{
+				"vault.hashicorp.com/agent-telemetry-prometheus_retention_time": "5s",
+				"vault.hashicorp.com/agent-telemetry-disable_hostname":          "true",
+			},
+			expectedValues: map[string]interface{}{
+				"prometheus_retention_time": "5s",
+				"disable_hostname":          true,
+			},
+		},
+		"common with some list annotations": {
+			annotations: map[string]string{
+				"vault.hashicorp.com/agent-telemetry-prefix_filter":             "[\"+vault.token\", \"-vault.expire\", \"+vault.expire.num_leases\"]",
+				"vault.hashicorp.com/agent-telemetry-maximum_gauge_cardinality": "3",
+				"vault.hashicorp.com/agent-telemetry-lease_metrics_epsilon":     "foo",
+				"vault.hashicorp.com/agent-telemetry-enable_hostname_label":     "true",
+			},
+			expectedValues: map[string]interface{}{
+				"prefix_filter":             []interface{}{"+vault.token", "-vault.expire", "+vault.expire.num_leases"},
+				"maximum_gauge_cardinality": float64(3),
+				"lease_metrics_epsilon":     "foo",
+				"enable_hostname_label":     true,
+			},
+		},
+	}
+	for name, tc := range tests {
+		t.Run(name, func(t *testing.T) {
+			pod := testPod(tc.annotations)
+			agentConfig := basicAgentConfig()
+			err := Init(pod, agentConfig)
+			require.NoError(t, err)
+			agent, err := New(pod)
+			require.NoError(t, err)
+			require.Equal(t, true, reflect.DeepEqual(tc.expectedValues, agent.Vault.AgentTelemetryConfig))
+		})
+	}
+}

agent-inject/agent/config.go

@@ -29,6 +29,7 @@ type Config struct {
 	TemplateConfig         *TemplateConfig `json:"template_config,omitempty"`
 	DisableIdleConnections []string        `json:"disable_idle_connections,omitempty"`
 	DisableKeepAlives      []string        `json:"disable_keep_alives,omitempty"`
+	Telemetry              *Telemetry      `json:"telemetry,omitempty"`
 }
 
 // Vault contains configuration for connecting to Vault servers
@@ -119,6 +120,57 @@ type TemplateConfig struct {
 	StaticSecretRenderInterval string `json:"static_secret_render_interval,omitempty"`
 }
 
+// Telemetry defines the configuration for agent telemetry in Vault Agent.
+type Telemetry struct {
+	UsageGaugePeriod                   string   `json:"usage_gauge_period,omitempty"`
+	MaximumGaugeCardinality            int      `json:"maximum_gauge_cardinality,omitempty"`
+	DisableHostname                    bool     `json:"disable_hostname,omitempty"`
+	EnableHostnameLabel                bool     `json:"enable_hostname_label,omitempty"`
+	LeaseMetricsEpsilon                string   `json:"lease_metrics_epsilon,omitempty"`
+	AddLeaseMetricsNamespaceLabels     bool     `json:"add_lease_metrics_namespace_labels,omitempty"`
+	FilterDefault                      bool     `json:"filter_default,omitempty"`
+	PrefixFilter                       []string `json:"prefix_filter,omitempty"`
+	StatsiteAddress                    string   `json:"statsite_address,omitempty"`
+	StatsdAddress                      string   `json:"statsd_address,omitempty"`
+	CirconusApiToken                   string   `json:"circonus_api_token,omitempty"`
+	CirconusApiURL                     string   `json:"circonus_api_url,omitempty"`
+	CirconusSubmissionInterval         string   `json:"circonus_submission_interval,omitempty"`
+	CirconusSubmissionURL              string   `json:"circonus_submission_url,omitempty"`
+	CirconusCheckID                    string   `json:"circonus_check_id,omitempty"`
+	CirconusCheckForceMetricActivation bool     `json:"circonus_check_force_metric_activation,omitempty"`
+	CirconusCheckInstanceID            string   `json:"circonus_check_instance_id,omitempty"`
+	CirconusCheckSearchTag             string   `json:"circonus_check_search_tag,omitempty"`
+	CirconusCheckDisplayName           string   `json:"circonus_check_display_name,omitempty"`
+	CirconusCheckTags                  string   `json:"circonus_check_tags,omitempty"`
+	CirconusBrokerID                   string   `json:"circonus_broker_id,omitempty"`
+	CirconusBrokerSelectTag            string   `json:"circonus_broker_select_tag,omitempty"`
+	DogstatsdAddr                      string   `json:"dogstatsd_addr,omitempty"`
+	DogstatsdTags                      []string `json:"dogstatsd_tags,omitempty"`
+	PrometheusRetentionTime            string   `json:"prometheus_retention_time,omitempty"`
+	StackdriverProjectID               string   `json:"stackdriver_project_id,omitempty"`
+	StackdriverLocation                string   `json:"stackdriver_location,omitempty"`
+	StackdriverNamespace               string   `json:"stackdriver_namespace,omitempty"`
+	StackdriverDebugLogs               bool     `json:"stackdriver_debug_logs,omitempty"`
+}
+
+// newTelemetryConfig creates a Telemetry object from the accumulated agent telemetry annotations.
+func (a *Agent) newTelemetryConfig() *Telemetry {
+	var tel Telemetry
+	if len(a.Vault.AgentTelemetryConfig) == 0 {
+		return nil
+	}
+	// First get it out of the map[string]interface{} which was created when we parsed the annotations.
+	telemetryBytes, err := json.Marshal(a.Vault.AgentTelemetryConfig)
+	if err != nil {
+		return nil
+	}
+	// Unmarshal it into a Telemetry object.
+	if err = json.Unmarshal(telemetryBytes, &tel); err != nil {
+		return nil
+	}
+	return &tel
+}
+
 func (a *Agent) newTemplateConfigs() []*Template {
 	var templates []*Template
 	for _, secret := range a.Secrets {
@@ -190,6 +242,7 @@ func (a *Agent) newConfig(init bool) ([]byte, error) {
 			},
 		},
 		Templates: a.newTemplateConfigs(),
+		Telemetry: a.newTelemetryConfig(),
 		TemplateConfig: &TemplateConfig{
 			ExitOnRetryFailure:         a.VaultAgentTemplateConfig.ExitOnRetryFailure,
 			StaticSecretRenderInterval: a.VaultAgentTemplateConfig.StaticSecretRenderInterval,

agent-inject/agent/config_test.go

@@ -766,3 +766,58 @@ func TestConfigAgentQuit(t *testing.T) {
 		})
 	}
 }
+
+func TestConfigTelemetry(t *testing.T) {
+	tests := []struct {
+		name              string
+		annotations       map[string]string
+		expectedTelemetry *Telemetry
+	}{
+		{
+			"annotations that exercise all of the types",
+			map[string]string{
+				"vault.hashicorp.com/agent-telemetry-prometheus_retention_time": "5s",
+				"vault.hashicorp.com/agent-telemetry-prefix_filter":             "[\"+vault.token\", \"-vault.expire\", \"+vault.expire.num_leases\"]",
+				"vault.hashicorp.com/agent-telemetry-maximum_gauge_cardinality": "3",
+				"vault.hashicorp.com/agent-telemetry-lease_metrics_epsilon":     "foo",
+				"vault.hashicorp.com/agent-telemetry-enable_hostname_label":     "true",
+				"vault.hashicorp.com/agent-telemetry-disable_hostname":          "true",
+			},
+			&Telemetry{
+				PrometheusRetentionTime: "5s",
+				PrefixFilter:            []string{"+vault.token", "-vault.expire", "+vault.expire.num_leases"},
+				MaximumGaugeCardinality: 3,
+				LeaseMetricsEpsilon:     "foo",
+				DisableHostname:         true,
+				EnableHostnameLabel:     true,
+			},
+		},
+		{
+			"everything empty",
+			map[string]string{},
+			nil,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			pod := testPod(tt.annotations)
+
+			agentConfig := basicAgentConfig()
+			err := Init(pod, agentConfig)
+			require.NoError(t, err)
+
+			agent, err := New(pod)
+			require.NoError(t, err)
+			// create sidecar config
+			cfg, err := agent.newConfig(false)
+			require.NoError(t, err)
+
+			config := &Config{}
+			err = json.Unmarshal(cfg, config)
+			require.NoError(t, err)
+
+			require.Equal(t, tt.expectedTelemetry, config.Telemetry)
+		})
+	}
+}